1. Field of Invention
This invention relates to optical micromachined or microelectromechanical system based multiplexers and multiplexing methods.
2. Description of Related Art
Multiplexers are generally well-known. For example, an optical multiplexer/demultiplexer comprising an array of optical waveguides is described in U.S. Pat. No. 5,002,350 to Dragone. For optical applications, an optical add/drop multiplexer receives an input optical signal with many optical channels at different wavelengths from a single optical fiber. The optical signal is demultiplexed into separate optical channels based on their wavelengths. Once demultiplexed, each of the separate optical channels can either pass through the optical add/drop multiplexer to a multiplexer or be dropped. For any channel that is dropped, a new signal can be added to utilize that channel. The passed and added channels are remultiplexed into an output optical signal sent out on a single optical fiber.
Current optical add/drop multiplexers are assembled from discrete components including demultiplexers, switches and multiplexers. Typical multiplexers and demultiplexers include diffraction gratings in free space optics and arrayed waveguide gratings for guided wave optics. Optical switches are used for dropping, adding and passing channels.
The systems and methods of this invention provide high quality optical multiplexing of an optical signal with improved performance.
The systems and methods of this invention separately provide optical multiplexers with improved manufacturability and reduced manufacturing costs.
The systems and methods of this invention separately provide optical multiplexers with reduced size and weight.
The systems and methods of this invention separately provide optical multiplexers with latching switches.
The systems and methods of this invention separately provide monolithic integration of optical multiplexers and demultiplexers with optical switches.
The systems and methods of this invention separately and independently provide a micro-optical device having an aligned waveguide switch.
According to various exemplary embodiments of the systems and methods of this invention, a silicon demultiplexer, a plurality of silicon switches and a silicon multiplexer are monolithically integrated on a single silicon chip. In embodiments, the silicon demultiplexer and the silicon multiplexer each comprise a diffraction grating. In other embodiments, the silicon demultiplexer and the silicon multiplexer each comprise an arrayed waveguide grating. In various exemplary embodiments, the silicon optical switches comprise 1xc3x972 or 2xc3x972 or mxc3x97n optical switches, optical changeover switches, micromachined torsion mirrors, electrostatic, magnetostatic, piezoelectric or thermal micromirrors, and/or tilting micromirrors.
According to various exemplary embodiments of the systems and methods of this invention, an optical signal is input into a monolithic reconfigurable optical multiplexer. The input optical signal comprises a data stream. The optical multiplexer includes at least one silicon demultiplexer, a plurality of silicon optical switches and at least one silicon multiplexer integrated on a single silicon chip. In embodiments, an optical signal is output that comprises a modified data stream.
According to various exemplary embodiments of the systems and methods of this invention, an optical communications system comprises an input optical fiber, a silicon demultiplexer communicating with the input optical fiber, a silicon multiplexer, a plurality of silicon optical switches communicating between the silicon demultiplexer and the silicon multiplexer and an output optical fiber communicating with the silicon multiplexer. The silicon demultiplexer, optical switches and multiplexer are monolithically integrated on a single silicon chip.
These and other features and advantages of this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the systems and methods according to this invention.